Remote login servers are extremely useful tools, particularly in environments in which users have accounts on many systems or where you want to centralize access to certain programs by running them on a single powerful computer that's accessed from less powerful systems. The most common Linux GUI environment, X, is inherently network-enabled, and so can be a good way to provide remote GUI access. There are several ways to configure remote access via X, including using a text-mode access protocol to "bootstrap" X-based tools or using an XDMCP server to authenticate a remote X server's user. Another option is to use VNC, which is more complex than a direct X connection from a networking point of view, but often simpler from a user 's point of view. There are several different ways to configure a VNC server to provide remote access, so the total range of options (via both direct X connections and VNC) is quite wide.